Midknight Blue® Agapanthus/ Lily of the Nile (Agapanthus x ‘Monmid’) Zones 6–10. If you’ve grown agapanthus before, you may have been frustrated getting these lovely South African natives to flower consistently or to overwinter successfully. Midknight Blue® establishes itself well, it has a nice deep green fleshy leaf, and the flower color is striking — it’s the deepest blue of any agapanthus.”